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Oxidations of volatile organic compounds such as toluene are catalyzed by CeO 2 (111) and proceeds with (a) the adsorption of the organic molecules and reaction of the lattice oxygen creating (b) an oxygen vacancy that is replenished by (c) re-oxidation of reduced ceria by gaseous oxygen. Similar mechanisms occur on (d) aliovalent-substituted ceria catalysts and (e) noble metal/ceria catalysts. • A review of the advances on ceria catalyst for VOC oxidation in the last 20 years. • In situ and operando studies confirms the importance of surface oxygen vacancies. • Increasing oxygen vacancies enhances catalytic activity. • Aliovalent-substitution can generate and stabilize defects and O 2 vacancies. • Noble metal (i.e., Au, Pt) facilitates the re-oxidation of reduced ceria. Based on unique oxygen storage capacity (OSC), ceria catalysts are widely investigated for remediation of volatile organic compounds (VOCs) over the recent decade. It is generally accepted that VOC oxidation on ceria is through Mars-van Krevelen mechanism, where lattice oxygen (O Lat) reacts with adsorbed VOC molecule, followed by re-oxidation of reduced ceria by replenishing O Lat from gaseous O 2. Oxygen vacancy and oxygen mobility are the key factors involved that influence the OSC and consequently modify the catalytic performance. Many strategies have been explored in the literature to optimize the materials. For the formation energy of oxygen vacancies varies with crystal orientation, ceria with specific morphologies (i.e., nanorods with (110) and (100)) perform better than the typical ceria catalysts. Beyond that, transition metal cations (e.g., V5+, Zr4+, Cr3+, Mnx+, and Cu2+) can dope or aliovalent substitute into ceria lattice, resulting in more defects and tuning the reactivity. Precious metal nanoparticles (e.g., Au, Pt, Pd, Ru) are known to activate the lattice oxygen at the interface of noble metal and ceria, facilitating the transformation of surface oxygen species and decreasing the light-off temperature. These strategies are also applicable to keep ceria from deactivation when facing chlorinated VOCs (CVOCs) and volatile sulfur compounds (VSCs). [ABSTRACT FROM AUTHOR]

In this study, we investigated the antibacterial properties of nanostructured Ag@SiO2–penicillin synthesized from triangular silver nanoplates (Ag NPs) against methicillin-susceptible S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) bacteria. The Ag@SiO2–penicillin nanoparticles contained approximately 33.2 wt% Ag as determined by ICP-OES. Grafting of about 2.8 wt% penicillin on Ag@SiO2 remarkably enhanced the bactericidal properties against MSSA and MRSA bacteria and showed no cell-death inducing effects towards the A431 cell line. [ABSTRACT FROM AUTHOR]

Nanostructured Ag@SiO 2 -Penicillin was synthesized from high-purity Ag0 NPs with a mean particle size of about 10 nm produced by electromagnetic levitation gas condensation (ELGC) method. The silver and penicillin contents of the synthesized nano-antibiotic were about 34 wt% and 2.5 wt% respectively, as determined by ICP-OES and TGA analyses. The antibacterial properties and synergistic effects of nanostructured Ag@SiO 2 and Ag@SiO 2 –Penicillin on killing the Methicillin-susceptible S. aureus (MSSA) and Methicillin-resistant S. aureus (MRSA) bacteria were also examined. The nanoparticles were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Ag@SiO 2 -Penicillin NPs showed an outstanding antibacterial activity compared to Penicillin and Ag@SiO 2 NPs. The Fractional inhibitory concentration (FIC) indexes were 0.54 and 0.52 against MSSA and MRSA bacteria respectively, illustrating the synergistic effects of Ag@SiO 2 -Penicillin NPs. In addition, Ag@SiO 2 -Penicillin NPs showed promising dose-dependent cytotoxicity effects indicating the protective effects emanating from anti-inflammatory properties of penicillin. • Ag@SiO 2 –Penicillin NPs have been prepared by cladding silver nano particles. • The prepared NPs have superior bactericidal properties against MSSA and MRSA compared to penicillin and Ag@SiO 2. • It is observed that the particles have significantly lower cytotoxicity than Ag@SiO 2. [ABSTRACT FROM AUTHOR]

• Polymeric membrane was used in a membrane reactor for ozonation treatment of DEET. • The membrane reactor equipped with membrane distributor, contactor and separator. • Coating the membrane contactor/distributor with PAC achieved greater DEET conversion. • The additional of ferrihydrite lead to deeper DEET mineralization. • Selective removal of water resulted in efficient treatment of DEET in membrane reactor. The ozone treatment of N,N -diethyl-meta-toluamide (DEET) in water was carried out in a membrane reactor that uses ozone-resistant polymer membranes for ozone distribution, catalytic contactor and water separation. Iron oxide (ferrihydrite) nanoparticles supported on powdered activated carbon (CAT1) were used as catalyst, and were coated on the surface of the membrane contactor/distributor. Ferrihydrites promote ozone dissolution and transformation to reactive hydroxyl radicals, and accelerate the conversion and mineralization of DEET. The powdered activated carbon helped retain the organic pollutants in the reaction zone leading to greater conversion and deeper mineralization. Consistently, the catalytic membrane contactor/distributor displayed the highest DEET conversion and TOC reduction over the entire studied range of ozone dosage and reaction residence time. The selective removal water by the membrane separator had the desired effect of concentrating the organic pollutants resulting in their improved treatment. The compact membrane reactor unit equipped with catalytic membrane contactor/distributor and membrane water separator outperformed a semi-batch ozone reactor with 60% DEET conversion compared to 20%, and 30% TOC reduction versus 5%. [ABSTRACT FROM AUTHOR]

Toluene oxidation on three ceria catalysts, CeO 2 , VO x /CeO 2 and Au/CeO 2 , was investigated by an operando Raman-online FTIR reactor cell. The reactive surface oxygen sites were preferred sites for vanadium and gold deposition. The deposited vanadium existed as V 5+ , while most of the gold was in Au + state and roughly a third of ceria was in the reduced Ce 3+ state. The Au/CeO 2 and CeO 2 catalysts (T 50 ∗  = 260 and 290 °C) were more active and selective toward the complete oxidation of toluene than VO x /CeO 2 catalyst (T 50 ∗  = 370 °C), where T 50 ∗ refers to the temperature for 50% of CO 2 yield. The η 2 -peroxide O 2 ads 2− was detected on Au/CeO 2 and CeO 2 catalysts, where toluene molecules preferentially adsorbed parallel to the surface via π-bonding. Au/CeO 2 gave complete combustion producing mainly CO 2 . On the other hand, η 1 -superoxide O 2 ads − was found on VO x /CeO 2 catalyst and the toluene molecule adsorbed via σ-bonding forming carbenium ions on the vanadia Brønsted acid sites. This catalyst produced significant amount of benzaldehyde as partial oxidation byproduct and CO (<25%). The nature of the active sites, configurational adsorption of toluene and the reactive oxygen species play important roles in the catalyst activity and selectivity leading to a large contrast in the catalytic behavior of the CeO 2 , VO x /CeO 2 and Au/CeO 2 catalysts. [ABSTRACT FROM AUTHOR]

Abstract: The photo-induced reactivity of three nanostructured titanium dioxides including TiO2 nanoparticles (i.e., nano-TiO2), titania–silica aerogel and nanotextured TiO2 film, were investigated for gas phase photocatalytic oxidation of trichloroethylene and inactivation of Bacillus subtilis and Escherichia coli microbial cells. A correlation was observed between photoreactivity for TCE conversion and bactericidal activity within TiO2 of similar nanostructures and composition (i.e., elemental and phase). This indicates that the photogenerated radical species from UV-irradiated TiO2 responsible for TCE photo-oxidation also play a major role in the inactivation of microbial cells. The superb bactericidal activities of titania–silica aerogels (i.e., up to 6log reductions in viable B. subtilis) and nanotextured TiO2 film (3.4log reduction) compared to commercial Degussa P25 TiO2 (0.64log reduction) and optimum nano-TiO2 (1.3log reduction) far exceeds the observed activity enhancement for TCE photo-oxidation. This implies that nanoscale chemical and structural environment also contribute towards the bactericidal activities. [Copyright &y& Elsevier]

Abstract: Gas permeable, photoactive and crack-free titania–silica aerogels of high titanium content (i.e., up to Ti/Si=1) were prepared by two-steps acid–base catalyzed method involving an acid-catalyzed prehydrolysis of silicon alkoxide followed by a base-catalyzed hydrolysis/condensation reactions with a chelated titania precursor. The prepared titania–silica aerogels displayed good mechanical strength (>30kNm−2), large surface area (>550m2/g), mesoporous structure (8–11nm) and good gas permeation. The porous aerogels trap and filter airborne particulates and the titania–silica aerogel have a fair performance for aerosol (65%) and bioaerosol (94%) filtrations. The photoactive anatase nano-TiO2 crystallized within the aerogel displays an order of magnitude higher reaction rate for UVA photooxidation of trichloroethylene compared to commercial Degussa P25 TiO2. The bactericidal activity of the titania–silica aerogel for Bacillus subtilis cells under UVA was also six orders of magnitude better. [Copyright &y& Elsevier]

Abstract: A composite membrane was prepared by coating high surface area γ-Al2O3 on the porous ceramic support of the ZSM-5 membrane. A thin layer of γ-Al2O3 was coated on the surface of the individual ceramic particles to increase the contact surface by about 50m2. Ozone treatment of phthalate contaminated water showed that ozonization with traditional sparger in a batch reactor yielded a 1.1% decrease in TOC, and simply replacing the sparger with a membrane distributor gave a 20% TOC removal. Providing a membrane contactor increases this value to 25%, while simultaneous membrane pervaporation of water resulted in 40% TOC degradation. This shows that it is possible to achieved enhanced ozone water treatment from a compact membrane reactor unit that uses the combined function of membrane as distributor, contactor and separator. [Copyright &y& Elsevier]

Abstract: Freestanding blocks of mesoporous, titania-silica aerogel catalyst were prepared and tested for gas phase photocatalytic oxidation of trichloroethylene (TCE) in a new photoreactor where the reactant gases flow through the aerogel block. The intimate contact between the reactants and catalyst resulted in a higher conversion. TS01 aerogel was prepared by ethanol supercritical drying, and contained nanometer-sized crystalline domains of anatase TiO2 (i.e., Tih name="sbnd" />Ti sites) within an amorphous Sih name="sbnd" />Ti and Sih name="sbnd" />Si network. The TS02 aerogel prepared by CO2 supercritical drying remained amorphous even after high temperature treatment, and analysis indicated that the Tih name="sbnd" />Si is the predominant site on this catalyst. The reaction results indicated that only the TS01 aerogel containing anatase TiO2 was active, but the formation of dichloroacetaldehyde on the amorphous Sih name="sbnd" />Si sites led to a rapid catalyst deactivation. However, a stable catalyst was obtained after these sites were passivated by ozone pretreatment under ultraviolet (UV) irradiation. The TS01 aerogel catalysts exhibited an average conversion of 30% and a quantum yield of 0.27 at a TCE concentration of 56ppm, feed flow rate of 40sccm and UV irradiation of 710μWcm−2. [Copyright &y& Elsevier]

Abstract: NH2–MCM-41 and COONa–MCM-41 were prepared by grafting aminopropyls and propionates on the pore wall of the mesoporous silica MCM-41 for the separation of and Cu2+. Single and binary component adsorptions show that has a 100% selectivity for adsorption at low pH (<3.5 i.e., point of zero charge, p.z.c.), while COO−Na+–MCM-41 adsorbs only Cu2+ over the entire pH range of the study (i.e., pH 1.5–5.5). Adsorption uptakes were rapid on both adsorbents reaching equilibrium in less than 3h and in most cases less than 10min. The adsorption capacity of for is high, approaching the theoretical values of two aminopropyls for one , the Cu2+ adsorption on COO−Na+–MCM-41 was less efficient requiring five propionates to adsorb one Cu2+. High purity hydrogen dichromate and copper chloride solutions were respectively recovered by a simple acid wash and the regenerated adsorbents were reused without a loss of performance. [Copyright &y& Elsevier]

Abstract: A novel membrane reactor was designed for the ozonolysis of refractory organic pollutants in water. The reactor employed a membrane contactor and a membrane separator in a concentric arrangement to affect a uniform ozone distribution along the reactor length, while allowing the simultaneous membrane separation and production of clean water. An alumina capillary membrane contactor and a ZSM-5 zeolite pervaporation membrane were used in this study. Using potassium hydrogen phthalate as model pollutant, the performance of the novel membrane reactor was tested and compared to ozone reaction carried out using the capillary membrane contactor and membrane pervaporation using the ZSM-5 membrane. The novel membrane reactor consistently outperformed both membrane processes. Forty-seven percent higher TOC degradation was observed compared to ozone reaction using a capillary membrane contactor. This enhancement is due to the increase in the organic pollutant concentration in the reaction zone as a result of water withdrawal by membrane pervaporation. As in the case of membrane pervaporation, clean water was produced at the permeate outlet of the novel membrane reactor. Clean water with less than 0.5±0.1ppm was collected from the membrane permeate outlet at a rate of 11–15kg−1 h−1 m−2. [Copyright &y& Elsevier]

Abstract: Freestanding and crack-free titania–silica aerogels with high titanium content (i.e., Ti/Si=1) were successfully prepared by adjusting the hydrolysis of the two alkoxide precursors to a comparable rate during the sol–gel processing. Two titania–silica aerogels were prepared by ethanol and CO2 supercritical drying methods. Well-dispersed, nanometer-sized anatase crystal domains (ca. 10nm) were crystallized by high temperature, ethanol supercritical drying. The crystalline domains were solidly anchored to the aerogel network by Ti–O–Si bonds. Titania–silica aerogels prepared by CO2 supercritical drying method were devoid of TiO2 crystals. A molecular-level mixing was achieved and anatase TiO2 was only crystallized with difficulty by high temperature calcination (1073K). Both aerogels were mesoporous and displayed similar open pore structure that is readily accessible to reactant molecules. However, only the titania–silica aerogel with anatase TiO2 prepared by ethanol supercritical drying was active for the gas phase, photocatalytic oxidation of volatile organic compounds (i.e., isopropanol and trichloroethylene). Catalysts prepared from Degussa P25 TiO2 displayed lower activity under similar reaction conditions. [Copyright &y& Elsevier]

Abstract: Two types of membrane reactors, the packed-bed membrane reactor (PBMR) and catalytic membrane reactor (CMR) were successfully miniaturized. Zeolites were incorporated as catalyst for reaction and membrane for separation. The membrane microreactors were tested for Knoevenagel condensation reaction between benzaldehyde and ethyl cyanoacetate to produce ethyl 2-cyano-3-phenylacrylate. Supra-equilibrium conversion and high product purity were obtained from selective removal of water during the reaction. A simple computation model was developed to simulate the reaction in the multichannel membrane microreactor using kinetic data from batch reaction, correlated data from membrane separation and published transport data. The influence of reactor geometry (i.e. channel width and membrane location), membrane separation and catalyst properties were evaluated and the results compared well with experimental data. The information provided by the model suggests several ways of improving the reactor performance. [Copyright &y& Elsevier]

Abstract: A multichannel membrane microreactor for continuous selective oxidation of aniline by hydrogen peroxide on TS-1 nanoparticles was successfully demonstrated. The high surface area to volume ratio that can be attained in the microreactor (3000m2/m3) facilitates the selective removal of water by-product, which reduces the effect of catalyst deactivation during the reaction. An improvement in the product yield and selectivity towards azoxybenzene was also observed. Azobenzene was obtained as by-product and its formation was attributed to homogeneous reaction of nitrosobenzene with aniline. Increasing temperature was beneficial for both yield and selectivity, but beyond 340K, microreactor operation was ineffective due to bubble formation and hydrogen peroxide decomposition. [Copyright &y& Elsevier]

Nanostructured TiO2 with 11- (P11) and 5-nm (P5) crystal sizes were prepared by a modified sol–gel method. Controlled crystallization and a pretreatment process were employed to obtain TiO2 with different surface roughness and degree of hydroxylation, while maintaining an identical crystal (i.e., 11 or 5 nm) and aggregate (i.e., 100 nm) sizes, phase structure (i.e., anatase), and crystallinity (i.e., X-ray diffraction peak intensity). Using the photooxidation of airborne trichloroethylene as a probe reaction, we were able to identify that the hydroxyl groups on low-coordinated titanium atoms are responsible for the generation of dichloroethylene and dichloroacetaldehyde by-products. Their presence usually means lower TCE conversion and in some cases leads to catalyst deactivation. [Copyright &y& Elsevier]

This work describes a versatile electrospinning equipment with rapid, independent, and precise x–y–z movements for large-area depositions of electrospun fibers, direct writing or assembly of fibers into sub-millimeter and micron-sized patterns, and printing of 3D micro- and nanostructures. Its versatility is demonstrated thought the preparation of multilayered functional nanofibers for wound healing, nanofiber mesh for particle filtration, high-aspect ratio printed lines, and freestanding aligned nanofibers. [ABSTRACT FROM AUTHOR]

Organic solar cell (OSC) development continues to demonstrate impressive device efficiency improvements. However, the materials synthetic simplicity essential to industrialization remains seriously lacking attention, imparting inferior performance records in low‐cost devices. Hence, low bandgap and completely non‐fused electron acceptors (CNFEAs) having simple molecular structures are investigated herein. In contrast to typically explored fused‐ring acceptors with smaller backbone conformational variations, minimizing the interface recombination sites through a greater extent of localized domains is identified as more critical in CNFEAs, leading to remarkable fill factors (FFs) approaching 75%, among the highest currently realized for low‐cost systems. However, this comes with diminishing charge generation efficiency. The general ternary blend optimization strategy modifying the morphology of host components is limited in preserving such remarkably high FFs. To suppress the trade‐off while keeping notable FFs, a new perspective of constructing functionally bridged components based on optical, electronic, and thermodynamic properties is introduced here. Specifically, charge generation is unrestrained from the host acceptor localized domains through the introduction of a "bridge" component while also taking advantage of the configuration to channel polarons toward the efficient transport moieties of the host components. Accordingly, this work incubates understanding‐guided optimizations toward the advancement of more practical devices. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Two new reaction products were identified from DEET ozonation. • Transformation pathway and kinetics for both DEET and products were determined. • Rapid conversion of DEET did not decrease the bioactivity of the treated water. • Ozonation of DEET caused the increase of microtoxicity due to the carbamate product. Abstract N , N -diethyl- meta -toluamide (DEET) is the active ingredient in many insect repellants against biting insects such as mosquitoes and ticks. It is one of the few micro-pollutants that are increasingly found in natural waters. The fact that DEET occurs in both influent and effluent of wastewater treatment works is indicative of its refractory nature. This work investigates the reactions of DEET with ozone, an oxidant that is becoming more common in treatments and disinfections of wastewater and drinking water. The transformation pathways were mapped, and a reaction model that accurately predicts the reactions was developed. The ozonation of DEET did not decrease the bioactivity of treated water, but instead resulted in a twofold increase in the microtoxicity. The findings suggest that the products of DEET ozonation has greater toxicity potentials compared to the parent compound posing a real hazard to human health and environment. [ABSTRACT FROM AUTHOR]

• MOF-based self-humidifying PEMFCs are demonstrated. • Dense and continuous MOF films were grown on porous substrate. • Subnanoliter of PFSA was confined to form PFSA/MOF structure composite membranes. • PEMFCs with new membranes exhibit excellent performances under dry feed conditions. A novel kind of confined PFSA/MOF composite membranes was developed to promote the water management within the membrane during the PEMFC operation. Two typical water-stable MOFs (i.e., ZIF-8 and MIL-101) were grown on the surface of polydopamine (PDA) or polydopamine/polyethyleneimine (PDA/PEI) modified perforated stainless steel meshes, and subnanoliter of PFSA was confined within the pores of as-prepared substrate. The composite membranes can be operated at high temperatures without external humidification. The PEMFC with confined PFSA/ZIF-8 composite membrane and confined PFSA/MIL-101 composite membrane exhibit three times higher power density than the one with commercial Nafion 117 membrane at 60 °C. The improved performance benefited from the good water retention capacity and thermal stability of MOF facilitating proton transfer and water management under high temperature and dry conditions. [ABSTRACT FROM AUTHOR]

Polystyrene (PS)‐dioctyl phthalate (DOP) films were prepared by spin coating solutions of a mixture of PS and DOP on Si wafers and characterized by time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) and X‐ray photoelectron spectroscopy (XPS). ToF‐SIMS depth profile results showed that DOP mainly segregated to the top 10 nm of the surface of the PS‐DOP film as well as to the interface between the film and the substrate. The normalized intensities of the ions corresponding to DOP on the surface increased as the annealing temperature increased and reached a maximum at the annealing temperature of 60°C, and then decreased as the annealing temperature increased. XPS results indicate that the maximum amount of DOP segregated to the top surface of the PS‐DOP film can reach to 39 wt% at the annealing temperature of 60°C. In addition, DOP evaporated at 25°C under ultra‐high vacuum conditions; hence, ToF‐SIMS and XPS analyses need to be carried out at low temperatures (e.g., −40°C). [ABSTRACT FROM AUTHOR]

SARS-CoV-2 remains one of the biggest global health problems, which has already reached our wastewater through fecal shedding by COVID-19 patients. While the development of vaccines has mitigated the threats of the COVID-19 pandemic, the evolutionary dynamics of SARS-CoV-2 in wastewater lack monitoring and understanding. In this study, SARS-CoV-2 variants in wastewater were identified by analyzing 8511 wastewater-derived genome sequences from 9 countries from March 2020 to May 2023. The dominance of co-circulating variants was observed, namely B.1 in 2020, Alpha and Delta in 2021, then superseded by Omicron lineages in 2022 with a three-times increase. Mutations were also profiled, revealing nearly 5031 unique amino acid substitutions occurring approximately 371,591 times, some of which were associated with enhanced viral transmission and fitness. This study provided the first long-term multi-country overview of the prevalence of co-circulating SARS-CoV-2 lineages and mutations in wastewater and showed its comparison with conventional epidemiological surveillance. The results highlight the ability of wastewater-based genome monitoring to supplement clinical surveillance efforts in rapidly detecting viruses up to the strain level to keep track of their potential transmission routes and evolutionary dynamics. [ABSTRACT FROM AUTHOR]

Defects were created on the surface of highly oriented pyrolytic graphite (HOPG) by sputtering with an Ar+ ion beam, then characterized using X‐ray photoelectron spectroscopy (XPS) and time‐of‐flight secondary ion mass spectrometry (ToF‐SIMS) at 500°C. In the XPS C1s spectrum of the sputtered HOPG, a sp3 carbon peak appeared at 285.3 eV, representing surface defects. In addition, 2 sets of peaks, the Cx− and CxH− ion series (where x = 1, 2, 3...), were identified in the ToF‐SIMS negative ion spectrum. In the positive ion spectrum, a series of CxH2+• ions indicating defects was observed. Annealing of the sputtered samples under Ar was conducted at different temperatures. The XPS and ToF‐SIMS spectra of the sputtered HOPG after 800°C annealing were observed to be similar to the spectra of the fresh HOPG. The sp3 carbon peak had disappeared from the C1s spectrum, and the normalized intensities of the CxH− and CxH2+• ions had decreased. These results indicate that defects created by sputtering on the surface of HOPG can be repaired by high‐temperature annealing. [ABSTRACT FROM AUTHOR]

Indoor exposure to volatile organic compounds (VOCs) is detrimental to the health of the occupants, and their removal is crucial in maintaining good air quality. Novel adsorbents prepared by modifying Metal-Organic Frameworks (MOFs), MIL101 (Cr), UiO-66, and UiO-66-NH 2 with [BMIM][CH 3 COO] ionic liquid, were characterized and tested for toluene adsorption. [BMIM][CH 3 COO]/MIL101 performed best with a fast sorption rate, large sorption capacity, and good regenerability. It displays synergistic interactions between the IL and MOF. Adding one weight percent [BMIM][CH 3 COO] to UiO-66 and UiO-66-NH 2 has a synergistic effect with respective 14% and 5% enhancements sorption over calculated values. The strong interactions between IL and UiO-66 and UiO-66-NH 2 , as observed in their thermogravimetric data, results in poor toluene sorption for 10 wt% [BMIM][CH 3 COO] loadings. This work provides a basis for IL modification of MOFs for enhanced sorption of VOCs for air treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

A cerium-doped Sb 2 S 3 anode is successfully fabricated for perfluoroalkyl acids (PFAAs) degradation via a hydroxyl radical dominant electrochemical oxidation (EO) coupled peroxymonosulfate (PMS) reaction. Various PFAAs can be efficiently removed within 25 min with high mineralization and low energy consumption. The hydroxyl radical, sulfate radical, and electron transfer are responsible for PFAAs degradation, and the hydroxyl radical played a dominant role. The electron can be moved from the highest occupied molecular orbital of these PFAAs to the lowest unoccupied molecular orbital of PMS via potential energy difference, further decomposing PMS to generate hydroxyl and sulfate radical for PFAAs degradation. Besides, the corresponding degradation pathway, defluorination, and Gibbs free energy of the reaction for each PFAAs were elucidated based on the identified intermediates and density functional theory calculations. The current study provides insight into the efficient decomposition mechanism of various PFAAs during EO and highlights its promising potential in environmental remediation. [Display omitted] • Electrochemical process can effectively remove various PFAAs. • The hydroxyl radical was responsible for the removal of PFAAs. • This electrochemical process shows strong tolerance to various changes. • PFAA degradation pathways are proposed. • The electron transfer process is clarified. [ABSTRACT FROM AUTHOR]

Iron complex regulated electrochemical reaction was triggered for revealing the reaction mechanism, degradation pathway, and applied potential of perfluorooctanoic acid (PFOA). The increased PMS concentrations, electrode spacing, and current density significantly enhanced PFOA elimination, with current density exhibiting a relatively strong interdependency to PFOA complete mineralization. The synergy between PMS and electrochemical reactions greatly accelerated PFOA decomposition by promoting the generation of key reaction sites, such as those for PMS activation and electrochemical processes, under various conditions. Furthermore, density functional theory calculations confirmed that the reciprocal transformation of Fe2+ and Fe3+ complexes was feasible under the electrochemical effect, further promoting the generation of active sites. The developed electrochemical oxidation with PMS reaction (EO/PMS) system can rapidly decompose and mineralize PFOA while maintaining strong tolerance to changing water matrices and organic and inorganic ions. Overall, it holds promise for use in treating and purifying wastewater containing PFOA. [Display omitted] • The electrochemical process was efficient in removing PFOA. • The electrochemical reaction mechanism was proposed. • The defluorination pathway was clarified. • Possible PFOA degradation pathways and toxicity were explored. [ABSTRACT FROM AUTHOR]

Abstract: Mesoporous silica MCM-41 was successfully prepared by flow synthesis in a microreactor at shorter reaction times (i.e., minutes versus day) at high yield (i.e., 60% calcined sample) to give particles of more uniform size and shape compared to MCM-41 prepared by conventional batch synthesis. Magnetic iron oxide nanoparticles were incorporated and organic amines (i.e., propylamine and propyl diethylene amine) were grafted to obtain magnetic mesoporous catalysts for the Knoevenagel condensation reactions of benzaldehyde with ethyl cyanoacetate, ethyl acetoacetate and diethyl malonate. The incorporation of magnetic nanoparticles and large organic amines can hinder reactants access to the catalyst resulting in lower reactivity. NH2-magMCM-41 showed superb catalyst activity and selectivity for the all three Knoevenagel condensation reactions studied. The catalyst can be easily dispersed into solution and rapidly removed by a magnet for recovery and reuse. [Copyright &y& Elsevier]

Abstract: Zeolites are increasingly used in fuel cell, from fuel conversion and conditioning to membrane additives as well as support for electrocatalysts. Zeolites’ ionic conductivity and capacity for water adsorption and retention were exploited to create zeolite and zeolite-PFSA proton conducting membranes for PEMFC. HZSM-5 micromembranes of different Si/Al ratios (from ∞ for Sil-1 to 30) were fabricated in a regular array on silicon followed by assembly and test for fuel cell performance. HZSM-5 with high aluminum content exhibits good proton conductivity and better PEMFC performance that approaches that of Nafion MEA. A rational approach in the design of structured HZSM-5-PFSA composite membrane was demonstrated. The PFSA was confined in subnanoliter volumes within zeolite sleeves to obtain self-humidifying membrane and enhanced PEMFC performance (i.e., up to nine-fold in MPD) at elevated temperatures (i.e., up to 100°C) and dry conditions. Higher water retention and improved membrane thermomechanical properties are believed to be responsible. [Copyright &y& Elsevier]

Abstract: Chromium (VI) oxyanions were removed selectively from various aqueous systems using magnetic MCM-41 nanosorbents of large surface area (>550m2 g−1) and high magnetization (≥8.0emug−1). 10nm magnetic iron oxide nanoparticles were embedded within 250±50nm MCM-41 to obtain a highly dispersible magnetic material, magMCM-41 that can be easily removed by a magnetic field. A highly selective nanosorbent was obtained by grafting aminopropyls and adsorbing Fe3+ on the pores of the magMCM-41. Chromium oxyanions were selectively removed over the pH range of 2–7 with high adsorption capacity of ca. 1.9mmolg−1 (ca. 100mgg−1) and K d >25,000mLg−1 for single and binary component adsorptions from distilled, tap, mountain stream and river waters. The presence of calcium in the tap and natural waters as well as humic compounds in mountain stream and river waters resulted in a slightly lower chromium adsorption, but did not affect its superb selectivity (ca. 97%). The adsorption and separation of the chromium oxyanions were adequately described by Freundlich and LeVan–Vermeulen equations. [Copyright &y& Elsevier]

Abstract: Freestanding Sil-1 and ZSM-5 micromembranes of Si/Al ratios ranging from 14 to ∞ were fabricated on silicon. The zeolite synthesis was adjusted to obtain micromembranes of similar microstructures (i.e., thickness, orientation, crystal grain size, morphology and intergrowth) and prepared membranes display comparable helium gas permeance. The low temperature removal of the organic TPA+ molecules by ozone enabled the preparation of low defect zeolite micromembranes that exhibit superb H2/nC4 (i.e., ≥100) and nC4/iC4 (i.e., ≥30) permselectivity ratios. The effects of aluminum content of the ZSM-5 micromembranes were investigated for single, binary and ternary gas permeation. Surface diffusion is important at low temperature and the single gas permeances of hydrogen, argon, nitrogen and methane were larger than Knudsen. The deviation from Knudsen increased with the Si/Al ratio and was largest for Sil-1. Propane–nitrogen separation in the zeolite micromembranes is mainly molecular sieving and display weak dependence on the aluminum content of the zeolite, where the separation of the ternary H2–CH4–CO2 mixture is by preferential adsorption and shows strong dependence on the Si/Al ratio of the zeolite. [Copyright &y& Elsevier]

Abstract: Freestanding blocks of binary oxides, TiO2–SiO2 aerogel containing highly ordered mesophase structures were successfully prepared by a new synthesis method involving partial solvent evaporation followed by supercritical extraction and drying. The new method allows the routine preparation of large, crack-free aerogels of high titanium content (i.e., Ti/Si⩽0.75 or up to 50wt.% Ti), ordered mesopores (i.e., 2–20nm), large surface area (i.e., 400–900m2 g−1) and pore volume (i.e., 0.7–2.6cm3 g−1). Aerogels with well-ordered mesopores were obtained for Ti/Si atom ratios of 0.04–0.08. The size of ordered mesopore domains decreases with increasing titanium loading, and TS75 aerogels with Ti/Si=0.75 display discontinuous microdomains of ordered mesoporosity within disordered phases interspersed with crystalline anatase TiO2. The greater permeability of the TS75 pore network resulted in fifteen times better activity for photocatalytic oxidation of airborne trichloroethylene compared to commercial Degussa P25 TiO2 and more than twice that TiO2–SiO2 aerogel (TS100) of similar titanium loading but with disordered and tortuous pore network. [Copyright &y& Elsevier]

Abstract: Selective gold adsorption was investigated for the NH2-MCM-41 and SH-MCM-41 adsorbents prepared by grafting aminopropyl and thiolpropyl groups on the surface of the MCM-41 mesoporous silica. The single component adsorption of gold, copper and nickel from salt solutions, and the binary adsorption studies of Au3+/Cu2+ and Au3+/Ni2+ solutions were carried out for the two adsorbents. Gold adsorption from simulated gold mining solution and gold electroplating wastewater were also reported. The NH2-MCM-41 and SH-MCM-41 displayed strong affinity for gold in the solution and both exhibited 100% selectivity for the gold in the binary Au3+/Cu2+ and Au3+/Ni2+ solutions. The NH2-MCM-41 is more suitable for the gold mining solution, while SH-MCM-41 is efficient for gold adsorption from the electroplating waste containing high amount of organics. The gold was recovered as high purity salt solution by elution with mineral acid for NH2-MCM-41 and thiolsulfate for SH-MCM-41. The regenerated adsorbent remained selective to gold and exhibited the same adsorption capacity as the fresh adsorbent. Also, the regenerated adsorbent performed well even after several reuses. [Copyright &y& Elsevier]

Abstract: A stain-based screening method was developed to screen different catalyst coatings for their germicidal activity. A Baclight dead/live bacteria viability kit (invitrogen, molecular probes) was used for staining the cell. The screening was carried out following a standard procedure. This included loading cell suspension to solid surface and maintaining contact for 30 min, then staining with a mixture containing dyes. The stained cells were observed using an epifluorescent microscope and photographed with a CCD camera under UV. Metal-doped TiO2 coatings on Al plates were prepared and tested for non-UV germicidal activity without using UV. It was tested using model microorganisms such as Bakers Yeast (Saccharomyces cerevisiae), Bacillus subtilis, Pseudomonas putida, and Escherichia coli. On the basis of the germicidal activity of catalyst and the degree of damage caused to the cells, the stained cells may appear green (viable), green with red or yellow nuclei and yellow (compromised) or red (nonviable). According to their stained color, cells were counted to calculate the percentage of dead, live, and compromised cells. Compromised cells are cells that grow very slowly after reculturing indicating a degree of reversible cell damage. Screening the germicidal activity using this staining method is accurate and efficient, and requires less time than the culture-based method. A modification to the procedure for measuring germicidal activity of rough surfaces or fibrous coatings was developed. Both TiO2 and metal-doped TiO2 (Ag, Pt, Au, Cu) possess non-UV based germicidal activity. The germicidal activity of TiO2 was found to be related with its wetting property and can be improved by UV irradiation before testing. It is not greatly affected by contact time, indicating a fast acting germicidal activity. [Copyright &y& Elsevier]

Abstract: Five silicalite-1 zeolite seeds of around 100nm, 600nm, 1.5μm, 3.0μm and 7.5μm were prepared. The preparation of porous α-alumina supports seeded using slip-casting technique and respective zeolite silicalite-1 membranes regrown by hydrothermal synthesis was investigated for different seed sizes. The effects of seed sizes on the formation of seed layers and zeolite membranes were studies in detail. It has been found that seed sizes have important effects on the formation of seed layers that determines the quality of regrown zeolite membranes. The seed layer and the regrown membrane from smallest seed (100nm) are most uniform and densest. With the increase of seed sizes (from 600nm to 3μm), the seed layers and the membranes become coarser and the intergrowth of the membranes becomes poorer. Increasing synthesis temperature favors improving the crystal intergrowth of the membrane, reducing the voids and changing the orientation of crystal growth. The zeolite particles with the size of 600nm and 1.5μm may act as seeds to form a continuous and uniform seed layer and membrane layer, whereas using zeolite seeds of 7.5μm, a continuous membrane cannot be obtained because of the formation of an incontinuous seed layer. [Copyright &y& Elsevier]

Abstract: A two-layered zeolite NaA-silicalite-1 membrane has been successfully prepared on a porous α-alumina tube by using seeded hydrothermal synthesis. The procedure involves pre-seeding with nanosized seed and subsequent regrowth by hydrothermal treatment. Single-layered NaA and silicalite-1 membranes were also synthesized for comparison. The membrane was composed of a silicalite-1 layer on top and a NaA layer on the porous support. SEM results of the membrane indicate that both the silicalite-1 layer and the NaA layer are uniform and well-intergrown. The silicalite-1 and NaA layers in the ‘sandwich’ mode have similar thickness of 3–4μm, whereas the thickness of their respective seed layer is different. The NaA seed layer is much thicker than the silicalite-1seed layer. This may be attributed to the different capillary action on the support and NaA layer during using a slip-casting seeding method. XRD analysis has also proved both zeolite NaA and zeolite silicalite-1 layers coexist in the dual-layered membrane. This method is also suitable for preparing other multi-layer zeolite membranes. [Copyright &y& Elsevier]

The effectiveness of low temperature ozone treatment for organic template removal from MFI zeolite membranes was investigated. The aim is to establish a convenient and reliable method for zeolite membrane activation that will ensure not only high gas permselectivity but also more importantly, good reproducibility. Fifty ZSM-5 zeolite membranes were prepared for the study. The effects of ozone concentration, treatment temperature, membrane thickness and compositions on the treatment process were examined. Half an hour treatment in oxygen mixture containing 50 g/m3 of ozone at 473 K is sufficient to remove all organic templates from 2 μm MFI zeolite membranes. Longer treatment time is needed for thicker membranes and for ZSM-5 with high aluminum concentrations. Membranes with excellent gas permeance and permselectivity were consistently obtained using this treatment method. Also, the membranes treated by ozone exhibit more reproducible membrane properties. [Copyright &y& Elsevier]

Silicon-glass microreactors with TS-1 catalyst wall coatings were fabricated and used for 1-pentene epoxidation with hydrogen peroxide in continuous flow. Seeding of the microchannels before zeolite growth was necessary to obtain a small crystal size and a sufficient zeolite film thickness. Crystal size was further reduced by adjusting synthesis conditions and utilizing triethoxymethylsilane (TEMS) as a crystal growth inhibitor. Zeolite film morphology and crystal orientation did not show any significant effect on reactor performance. However, reaction rate was found to increase with decreasing TS-1 crystal size in the zeolite films and with increasing amount of tetrahedrally coordinated Ti(IV). Catalyst deactivation was observed, caused by the presence of organic compounds and Ti leaching from the microporous framework. [Copyright &y& Elsevier]

Zeolite powders and films were prepared from six published synthesis recipes claimed to produce zeolite film coatings and membranes with (2 0 0), (0 2 0), (0 0 2) and (1 0 1) orientations. The morphology and orientation of the zeolite films prepared from each synthesis recipe were characterized and compared to determine the influence of synthesis composition and crystallization conditions. The zeolite growth environment was manipulated by changing the seed concentration on the substrate. The experimental results indicate that the synthesis chemistry and crystallization conditions affect the crystal grain morphology, whereas the growth environment influences the crystal habit. A simple method for predicting the orientation of the zeolite film based on the morphology of the zeolite crystal and the growth environment is also presented. [Copyright &y& Elsevier]

We studied the time‐of‐flight secondary ion mass spectrometry fragmentation mechanisms of polystyrenes—phenyl‐fluorinated polystyrene (5FPS), phenyl‐deuterated polystyrene (5DPS), and hydrogenated polystyrene (PS). From the positive ion spectra of 5FPS, we identified some characteristic molecular ion structures with isomeric geometries such as benzylic, benzocyclobutene, benzocyclopentene, cyclopentane, and tropylium systems. These structures were evaluated by the B3LYP‐D/jun‐cc‐pVDZ computation method. The intensities of the C7H2F5+ (m/z = 181), CyPent‐C9H3F4+ (m/z = 187), CyPent‐C9H4F5+ (m/z = 207), and CyPent‐C9H2F5+ (m/z = 205) ions were enhanced by resonance stabilization. The positive fluorinated ions from 5FPS tended to rearrange and produce fewer fluorine‐containing molecular ions through the loss of F (m/z = 19), CF (m/z = 31), and CF2 (m/z = 50) ion fragments. Consequently, the fluorine‐containing polycyclic aromatic ions had much lower intensities than their hydrocarbon counterparts. We propose the fragmentation mechanisms for the formation of C5H5+, C6H5+, and C7H7+ ion fragments, substantiated with detailed analyses of the negative ion spectra. These ions were created through elimination of a pentafluoro‐phenyl anion (C6F5−) and H+, followed by a 1‐electron‐transfer process and then cyclization of the newly generated polyene with carbon‐carbon bond formation. The pendant groups with elements of different electronegativities exerted strong influences on the intensities and fragmentation processes of their corresponding ions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Efficient microwave-assisted flow synthesis of TiNS and their transformation to TiNT. • Visible-light photocatalyst from nano-confinement of platinum clusters in TiNT. • Deep photocatalytic oxidation of diclofenac by Pt-TiNT mitigate toxicity. • Enhanced quantum efficiency of Pt-TiNT compared to parent TiNT. Pt-TiNT with PtO nanoparticles dispersed within the lumen and interlayer spaces of titania nanotubes (TiNT) were prepared by a new process involving titanate nanosheets (TiNS) synthesis in an optimized microwave-assisted flow reactor, followed by ion-exchange with a Pt precursor, before triggering the titanate layer rolling to trap the Pt precursor clusters inside the titania nanotubes, followed by a thermal treatment. TEM, XRD, and Raman analyses confirm the total conversion of TiO 2 into TiNS in 15 min at 120 °C and 4 bar, and the TiNS transformation into 181 nm-long TiNT with 10 and 6 nm outer and inner diameter, respectively. The 2% Pt-TiNT comprises 0.7 nm PtO clusters (according to XPS), causing slight distortions of the interlayer spaces, while a few larger 2–3 nm Pt clusters reside within the lumen. As a result, Pt-TiNT is 14-fold more active than TiNT for visible light (400–780 nm) photocatalytic oxidation of diclofenac under 2136 μW·cm−2 irradiation, and>1000-fold better than the uncatalyzed photoconversion reaction under 100 mW·cm−2 artificial solar lighting. In addition, nano-confinement of PtO clusters narrowed the bandgap of the TiNT, which, combined with its excellent absorptivity to harvest light, allowed a broader spectral range of photon energies to activate the photocatalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ciprofloxacin and clarithromycin were detected in KTR water. • Antibiotic persistence gives rise to antibiotic-resistance genes and bacteria. • PbO 2 electrode showed good stability and activity on antibiotics removal. • The generated SO 4 − and OH radical can efficiently degrade antibiotics. • The electron transferred from antibiotics to the SO 4 2−. The widespread occurrence of antibiotics in the environment is a global problem, but their occurrence and spatiotemporal distribution, as that of their associated antibiotic-resistant genes and bacteria in Hong Kong estuaries and coast, are poorly understood or documented. Here, the long-term influences of ciprofloxacin (CIP) and clarithromycin (CLR) along the Kai Tak River (KTR) nullah, a man-made channel transporting treated effluents from two wastewater treatment plants, were monitored from December 2019 to April 2021. The results revealed that these antibiotics were widely distributed, exhibiting seasonal variations around median concentrations of 1693.8 ng L−1 for CIP and 632.1 ng L−1 for CLR. The ecological risk assessment indicated that ciprofloxacin and clarithromycin are the predominant ecological risk contributors to aquatic organisms in KTR water. The antibiotic resistance genes (ARGs) of acrB-1, acrA-2, mexF, acrA-1, and mexE persist in the sampled water along with CIP, CLR, and CIP/CLR-resistant bacteria. In addition, a PbO 2 thin film electrode of superb stability and electrochemical activity was fabricated by an electrodeposition method and used for the electrochemical oxidation of antibiotic water pollutants. As a result, CIP and CLR were rapidly removed and degraded within fifteen minutes by electron transfer and reactive oxygen species, thus, mitigating ARG contamination in the nullah. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nano-hierarchical designed structures for sustained condensate mobility at high subcooling. • Nano-hierarchical surface repels condensate infiltration to maintain superhydrophobicity. • Attains 60% increase in heat transfer rate even at high surface subcooling. Superhydrophobic nanostructured surfaces can enhance water condensation efficiency by facilitating droplet departure via coalescence-induced jumping. However, condensed droplets tend to transit from a mobile jumping mode to a highly pinned state at high condensation heat flux because excessive water nucleates within the nanostructures and anchors the condensed droplets. The large pinned droplets act as a thermal barrier and insulate the cooling surface, thus severely degrading its heat transfer efficiency. This work developed a nano-hierarchical structured surface by growing branched TiO 2 nanorod arrays to prevent condensation-induced droplet pinning. After hydrophobization, the nano-hierarchical structure can spontaneously push the water out of nanostructures with an outward Laplace capillary pressure gradient when the droplet size is only at the nanoscale level. This effective de-wetting process maintains the high droplet mobility on the nano-hierarchical surface over a wide subcooling range, resulting in an up to ∼ 90 % increase in heat transfer coefficient at a high heat flux of 132 kW∙m−2 compared to the single-tier nanorod surface. Our investigation of how the nano-hierarchical structures fundamentally suppress the condensation-induced wetting on superhydrophobic surfaces represents a significant advance in understanding multiphase wetting phenomena and paves the way for the rational design of cooling surfaces. [ABSTRACT FROM AUTHOR]

Toluene is a prevalent pollutant in indoor environments and its removal is essential to maintain a healthy environment. Adsorption is one of the best alternatives for organic vapours removal, specially at low indoor concentrations. Metal Organic Frameworks (MOFs) and Ionic Liquids (ILs) are potential materials for this mean. In this work, the synthesis and application of IL/MOF composite materials for toluene removal is reported. Loading [BMIM][CH 3 COO] ionic liquid into MIL101 porous structure improves parent materials affinity towards toluene capture by two orders of magnitude (as Henry's constants, attesting to their synergy). MIL101(Cr) and absorption in [BMIM][CH 3 COO] IL is best described by Henry's Law, while the Langmuir adsorption model predicts toluene adsorption on [BMIM][CH 3 COO]/MIL101(Cr) better than Freundlich and Toth equations. Diffusional and kinetics models revealed that toluene diffusion is the rate limiting step for pristine MIL101. Kinetic and diffusion rates were systematically improved upon the incorporation of the ionic liquid due to shorter toluene hops with the adsorbed IL and the increased hydrophobicity in the composites making the sorption more favourable. This study provides a systematic analysis and modelling of the toluene capture process in IL/MOF composites aiding a better understanding of the sorption process in these novel materials. [ABSTRACT FROM AUTHOR]

Aiming to enhance the stability of noble metal nanoparticles that are anchored on the surface of colloidal carbon spheres (CCSs), we designed and prepared a new kind of sandwich-structured ZIF-8@Pd-CCS microsphere. Typically, uniform CCSs were first synthesized by the aromatization and carbonization of glucose under hydrothermal conditions. Subsequently, noble metal nanoparticles, herein Pd nanoparticles, were attached to the surface of CCSs via self-reduction route, followed by in situ assembly of a thin layer of ZIF-8 over the Pd nanoparticles to form the sandwich-type ZIF-8@Pd-CCS microspheres. X-ray diffraction (XRD) patterns and Fourier transform infrared spectroscopy (FTIR) spectra confirmed the presence of crystalline ZIF-8, while TEM analysis revealed that the ZIF-8 shells were closely bound to the Pd-loaded CCSs. The shell thickness could be tuned by varying the ZIF-8 assembly cycles. Further, liquid-phase hydrogenation of 1-hexene as the probe reaction was carried out over the ZIF-8@Pd-CCS microspheres and results showed that the prepared microspheres exhibited excellent agglomeration-resistant and leach-proof properties for the Pd nanoparticles, thus leading to the good reusability of the ZIF-8@Pd-CCS microspheres. [ABSTRACT FROM AUTHOR]

A ZIF-8/NaA composite membrane microreactor was fabricated on multi-channel stainless steel plate. NaA zeolite membrane was first introduced into the microchannel as a modification layer via a secondary growth. Subsequently, a layer of ZIF-8 membrane was grown over the NaA zeolite layer as a catalytic layer by using ZnO-induced synthesis method. Such ZIF-8/NaA composite membrane microreactor was applied in continuous flow Knoevenagel condensation of benzaldehyde and ethyl cyanoacetate. Nearly 100% product yield was achieved in a short residence time under mild conditions. Importantly, no obvious deactivation was observed even after 50 h, indicating its excellent stability. [ABSTRACT FROM AUTHOR]

We demonstrate the preparation of sandwich structured microspheres containing Fe 3 O 4 cores, inner silica shells, supported Pd nanoparticles and outer ZIF-8 shells. The synthesis involved first deposition of silica layer on magnetic cores through traditional Stöber method and subsequent immobilization of Pd nanoparticles on the silica surface via grafting techniques, followed by the assembly of ZIF-8 shells over the Pd nanoparticles. Uniquely, the noble metal nanoparticles are sandwiched between the silica shell and porous ZIF-8 shell and such a configuration allows the metal nanoparticles to remain stable against aggregation and leaching while at the same time they are selectively accessible to the external environment outside of the ZIF-8 shells. Also, the resulting core@double-shell microspheres exhibit a superparamagnetic behavior with a high saturation magnetization of ~36.7 emu/g inheriting from the magnetic Fe 3 O 4 cores. It is believed that the designed microspheres could find potential uses in heterogeneous catalysis and adsorption fields with excellent reusability and high efficiency. [ABSTRACT FROM AUTHOR]

Diagnosis of Alzheimer's disease (AD) can be performed with the assistance of amyloid imaging. The current method relies on positron emission tomography (PET), which is expensive and exposes people to radiation, undesirable features for a population screening method. Magnetic resonance imaging (MRI) is cheaper and is not radioactive. Our approach uses magnetic nanoparticles (MNPs) made of superparamagnetic iron oxide (SPIO) conjugated with curcumin, a natural compound that specifically binds to amyloid plaques. Coating of curcumin-conjugated MNPs with polyethylene glycol-polylactic acid block copolymer and polyvinylpyrrolidone by antisolvent precipitation in a multi-inlet vortex mixer produces stable and biocompatible curcumin magnetic nanoparticles (Cur-MNPs) with mean diameter <100 nm. These nanoparticles were visualized by transmission electron microscopy and atomic force microscopy, and their structure and chemistry were further characterized by X-ray diffraction, thermogravimetric analysis, X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry, and Fourier transform infrared spectroscopy. Cur-MNPs exhibited no cytotoxicity in either Madin–Darby canine kidney (MDCK) or differentiated human neuroblastoma cells (SH-SY5Y). The P app of Cur-MNPs was 1.03 × 10 −6 cm/s in an in vitro blood–brain barrier (BBB) model. Amyloid plaques could be visualized in ex vivo T2*-weighted magnetic resonance imaging (MRI) of Tg2576 mouse brains after injection of Cur–MNPs, and no plaques could be found in non-transgenic mice. Immunohistochemical examination of the mouse brains revealed that Cur-MNPs were co-localized with amyloid plaques. Thus, Cur–MNPs have the potential for non-invasive diagnosis of AD using MRI. [ABSTRACT FROM AUTHOR]

A high-permeance ZIF-8 membrane was successfully synthesized on the inner side of a porous hollow fiber ceramic tube in a simple flow system via in situ direct growth method. The continuously pumping fresh nutrients through the inner-surface favor increasing the heterogeneous nucleation of ZIF-8 crystals and the formation of continuous ZIF-8 membrane, thus leading to a high performance ZIF-8 membrane. The achieved ZIF-8 membrane was thin and dense, and has only a thickness of about 2.5 μm. The membrane demonstrated remarkably high H 2 permeance of 1.9 × 10 −6 mol m −2 s −1 Pa and excellent molecular sieving performance with H 2 /N 2 , and H 2 /CH 4 ideal selectivities of 12.9 and 15.6, respectively. [ABSTRACT FROM AUTHOR]

• PFOS degradation can keep a high level by electrochemical oxidation. • Electrochemical oxidation was effective to multiple organic contaminants. • DFT calculations confirmed electron can be transferred from PFOS to PMS. • Ti4O7 could serve as the conductive bridge to promote the electron transfer. • The ultrasonic treatment can effectively active electrode for PFOS degradation. Polyfluoroalkyl and perfluoroalkyl chemicals (PFCs) widely used in lubricants, surfactant, textiles, paper coatings, cosmetics, and fire-fighting foams can release a large deal of organics contaminants into wastewater and pose great risks to the health of humans and eco-environments. Although advanced oxidation processes can effectively deconstruct various organic contaminants via reactive radicals, the stable structure of PFCs makes it difficult to be degraded. Here, we confirm that electrochemical oxidation process coupled with peroxymonosulfate (PMS) reaction can efficiently destroy stable structure of PFCs via electron transfer and meanwhile completely degrade PFCs via generated active radicals. We further studies via capturing and scavenging radicals, and DFT calculations find that electron hydroxyl radials play a dominant role in degrading PFCs. Based on the calculations of adsorption energy and molecular orbital energy we further demonstrate that many active sites on the surface of Ti 4 O 7 (1 0 4) plane can rapidly take part in electrochemical reaction for generating radials and removing organic contaminants. These results give a promising insight towards high-effective and deep degradation of PFCs via electrochemical reaction coupled with advanced oxidation processes, as well as providing guidance and technical support for the remove of multiple organic contaminants. [Display omitted] [ABSTRACT FROM AUTHOR]

Inthis work, we fabricated a new type of Pd/SiO2@ZIF-8core–shell catalyst composed of a Pd/SiO2microsphereas the core and a ZIF-8 membrane as the shell. The preparation procedureinvolves first loading Pd nanoparticles onto nonporous SiO2microspheres to obtain the Pd/SiO2core and then coatinga perfect layer of ZIF-8 shell on the core by electrostatic inductionto form a Pd/SiO2@ZIF-8 core–shell structure. Itis crucial that the modification of the Pd/SiO2core withpolyelectrolyte was employed to improve the charge distribution ofthe core surface and preferably adsorb Zn2+cations inthe synthesis solution so as to assist the formation of a continuousZIF-8 shell. The compactness and thickness of the shell were optimizedby increasing the number of cycles of ZIF-8 growth. The hydrogenationsof alkenes with different molecular sizes showed that the Pd/SiO2@ZIF-8 catalysts can provide excellent product selectivityand antipoisoning and antileaching properties for the hydrogenationsof alkenes. [ABSTRACT FROM AUTHOR]

A newZIF-8 membrane architecture with high performance supportedon vertically aligned ZnO nanorods was successfully prepared. Thevertically aligned, single crystal ZnO nanorods were grown seamlesslyfrom porous ceramic support to form an intermediate support layerfor the ZIF-8 membrane. They provide multiple anchorages for the ZIF-8membrane that are both strong and flexible. The nanorods were activatedto induce a uniform nucleation of ZIF nuclei on their surface to initiateand guide the growth of a defect-free ZIF-8 membrane. Single gas permeationsand binary separations carried out to investigate the transport propertiesof these new membrane architectures confirmed that the ZIF-8 membraneswere free of defects and stable at a higher temperature (473 K). [ABSTRACT FROM AUTHOR]